Elastic packing-ring.



E. R. GILL.

ELASTIC PACKiNG RING. APPLICATION FiLED JULY 26.12MB.

Patented Dec. 26,1916.

ywem rox rings as have EDWIIF B. GILL, 0F YQNKERS, NEW YORK.

ELASTIC PACKING-RING.

Specification of letters Patent.

Patented Dec. 26, 916.

Application filed July 26, 1915. Serial No. 41,871.

To all whom it may concem:

Be it known that I, EDWIN R. GILL, a citizen of the United States, residing at Yonkers, in the county of Westchester and State of New York, have invented certain new and useful Improvements in Elastic aching-Rings; and I do hereby declare the following to be a full, clear, and exact de scription of the invention, such as will enable others skilled in the art to. which it appertains to make and use the same.

Packing rings for air compressors, steam engines, high pressure pumps, gas engines, etc, have been made hitherto of more or less resilient metal adapted to be sprung over a piston and into grooves surrounding the piston adapted to accommodate such rings.

hese rings are counted upon to produce a fluid-tight fit at all times, by reason of their pressing outward so as to hug the inner surface of the cylinder in which the piston moves; and theoretically this tight fit is preserved by the actual expansion of the rings to compensate for wear within the cylinder. In practice, however, the expansion of such been commercially used is accompanied by an opening of the joint, where the ends of the ring come together, which permits the fluid under pressure to find its or by both of these paths.

such devices are not way past the ring; either over its outer face, under it and through its containing groove, Various plans have been proposed for overcoming this difficulty by making the ring in two or more pieces; but I have found in practice that only expensive as compared with one-piece rings, but fail of c0mplete success where subjected to high pressures.

My present invention relates to an improved one-piece rin which I have found to be highly success 111 in practice in preventing all leakage past the ring under conditions of wear. This ring len s itself to a particularly favorable process of manufacture which is also a feature of my invention, and has been claimed in my U. S. Patent No. 1188370, dated June 20th, 1916.

My improved ring isparticularly advantageeue in its application to internal combustion engines wherein it is necessary to produce sudden high compression, and then successfully to confine a body of the very hot gases produced by explosion under excessivelyhigh pressures. In these engines, too, the proper lubrication of the interior of the cylinder is highly important, while at the same time it is highly desirable for many well known reasons to avoid any excess of lubricating oil being exposed. to the interior burning gases. I have found that my improved ring fully meets these requirements of internal combustion engines even when applied to old machines whose cylinders have been deformed by use. Furthermore I have found that fewer rings are required on a iven pistonwhen my improved joint is use This fact conduces to chea ness and to lightness of construction; t e latter advantage being important more paritifiularly in engines for aeroplanes and the 1 e. The preferred perfected form of my ring is illustrated in the accompanying drawings, wherein Figure 1 is a plan or face view of the ring partly open. Fig. 2 is a perspective view of the completely closed ring and Fig. 3 is a similar view of the finished joint in open position.

Some manufacturers of packing rings adopt a form wherein the inner and outer cylindrical limiting surfaces are mutually.

eccentric, in the belief that this arrange ment is favorable to uniform pressure upon the confining walls of the cylinder within which the piston. moves. Others deem this a fallacy, and use thickness. Some of these latter resort to systems such asa graduated peening or the like for producing a supposed uniformity of outward pressure. My improved joint may be used with rings of any of these classes, and I have shown it as employed on a ring having a substantially uniform cross section.

The process of manufacturing my ring and the advantages of the ring in its adaptation to said process are described in my aforesaid Patent Number 1188376, The ring rings of uniform radial as completed by said process is claimed herein and has the following characteristics: The ring 10 has a joint formed by laterally overlapping cheek pieces 11 and 12, each having an underhung projection, 13, 14. Behind and at one side of each cheek piece there is provided a suitable recess, 15, 16, preferably closed at its base by a short inward circular arc, and the underhung projections are shaped to enter said recesses when the ring is part1 T or wholly closed, as shown in Figs. 1 an 2. The underhung projections have upper surfaces which taper or have an inward departure from the normal circular form. Thisis best shown somewhat exaggerated for the sake of clearness in Fig. 1, and the bestmode of producing the taper in question is fully set forth in my said Patent No. 1188370. I

Considered both from the point of view of the above process and from that of successfully preserving a tight joint against fluid under-high pressure, the tapering of the underhung projections is of vital importance.

I have found, after many experiments, that rings of the general character described herein cannot be successfully made and used,

save to a very limited extent, where the upper surfaces of these underhung projections are formed in the natural and more obvious way; that is to say, are struck upon the arc of a circle concentric with the ring. Under usual conditions, when these parts are so made, they are very apt to break off, either when the. blank is compressed into the position shown in F of use, I have found that this difficulty can be avoided by slightly tapering the upper surfaces of these underhung pro ections, andthat the best results as to perfect fit are obtainable by curving these surfaces in accordance with the following theory: \Vhen a ring begins to expand under conditions'of wear, the outer portions of the ring are continually supported, guided and formed by the circular contour of the working cylinder. It follows from this that the outer surfaces of the ring, as it expands, conform substantially to a continually expanding circle. In other words, the circular form is constantly maintained by the control of the confining cylinder walls, circle slowly increases. The underhung projections, however, act as cantalivers and remainor tend to remain-in their original form, while they slowly change their direction with relation to the tops of the recesses 15 and 16 It is this condition or tendency which seems to be responsible for the frequent breakage of these projections when their upper surfaces are struck on a circle.

- It is obvious that by. the tapering ofthese ig. 2, or after asshort period while the diameter of the surfaces is meant a suitable inward departure from the normal circle drawn through the point where the upper surface of each underhung projection springs from the body of the ring. This departure may conform to a curve or may in some cases be substantially a straight line.

The best curvature to be given to the fitting surfaces is determined in each case by the theory and practice which isset forth in my said Patent No. 1188370. I do not limit myself to a structure wherein absolute theoretical perfection of curve is found, as

this is not essential to a considerable degree v of success.

It will be seen that my improved joint prevents passage of fluids under pressure across the plane of-the ring by reason of the constantly overlapping cheek pieces making close sliding contact on their meeting faces. At the same time penetration of the fluid under the ring is constantly opposed by the contact between each underhung projection and the top of the corresponding recesses 15 and 16.

What I claim is- 1. An elastic packing ring having a joint formed by two meeting ends having cheek pieces adapted to overlap side by side and fitted together with sliding contact, each meeting end of said ring having a suitably formed recess behind and opposite its own cheek piece and opposite the cheek piece on the other meeting end, and each cheek piece having a slightly tapering underhung projection formed by an extension of its inner portion and adaptedto slidev within, its i-opposite recess while preserving a close fit with the top of said'recess.

2. Anelastic packin'gring havingajoint formed by two meeting ends having ch k pieces adapted to overlap side by side and io fit together with sliding contact, said check pieces each having behind and at one side of it a suitable recess and each having an underhung projection formed by an extension of its lower part whose upper surface slopes slightly toward the center of the ring to adapt it to preserve a proper fit with the top of its opposed recess.

3. An elastic packing ring having a joint formed by two meeting ends having cheek pieces adapted to overlap side by side and fit together with sliding contact, said check pieces having substantially one half the thickness of the ring and each remaining half thickness presenting a recess behind and at one side of the corresponding cheek pieces closed at its base by a short inward circular arc, and slightly tapering underhung projections formed by extensions'of the inner portions of said cheek pieces, adapted to preserve a sliding fit with said recesses respectively, substantially as deably formed recesses adapted to receive said scribed. projections and to form a tight fit there- 4. An elastic packing ring having a joint with when the joint is closed by compress-m 10; formed by overlapping cheek pieces having of said ring. 5 underhung projections Whose upper surfaces In testimony whereof I afiix my signature.

are formed to depart inward from the nor 7 v mal circular form, said ring having suit- EDWIN R. GILL. 

